Diesel in oil

[disco gazza]

Hi all,
Hope everyone had a merry christmas and a happy & safe new year..:D

The last couple of oil changes that I've done,there appears to be a small(like small button size) of a blue-green colour in the oil when I check what the oil is like from the filter.
I'm guessing that its diesel,but I could be wrong.
Beast is a 92 TDi with 356,000 on it.
On start up,there's no smoke.
Uses same amount of oil( its normally down near the fill mark on dipstick),previous TDi was the same.
Change oil every 5-6 tho including filter.

Is it time for a bit of an overhaul maybe?
Your thoughts would be greatly appreciated

cheers

[Jock The Rock]

Hey mate

If you can see a green button in the oil it would have to be coolant. If it were diesel it would mix with the oil and the only way you could notice would be smell or the level on your dipstick would go up

There are two possibilities I can think of, maybe slight leak of head gasket or (not sure if 200 Tdis do but 300 Tdis do) a leaking oil cooler. The oil cooler is located in one of the tanks of the radiator.

There may be other sources but they would be the places I'd look first

JC is the man to ask, he has a lot more experience on 200 Tdis than me

I reckon you can squeeze a few more ks out of it than that, possibly worth doing a head gasket as a precautionary measure at that many ks though

[oldyella 76]

If you want to test for fuel in the oil, drop a bit of oil off your dipstick onto a piece of brown paper. If you have diesel fuel in the oil if will show a dark spot in the centre (engine oil) and a lighter area outside the centre which will be diesel fuel. This is because the lube oil will stain the centre and the diesel fuel being lighter will move to the outside of the darker oil stain.
Hope this helps.
Lindsay.

[disco gazza]

Thanks for the responses guys.
Will check out the drop of oil on brown paper when I find a bit of brown paper lol.

JC Feel free to give me some hints please.

cheers

[justinc]

Well, if it matches the colour/ shade of your coolant then Jock is on the money. With a 200 Tdi there are places water can enter the crankcase, other than the head. If it were the head gasket, or a crack in the head in the usual places then pressurisation will usually occur, but sometimes the leak can be from a coolant gallery across to a pushrod gallery, too. At those KM's I'd be changing out the head gasket anyways.

The front timing cover/ case can corrode through in places, allowing coolant to drip into the sump, however finding this is easier said than done, complete removal of the timing case will be required to find the fault :(

If you have access to a pressure tester, then this is the best thing for testing the system.

Be careful though, stay below or at the max system pressure when testing, 15psi.

JC

[disco gazza]

Well I found a bit of brown paper and the results were.... no separation of oil from dipstick. :D

Soooo
a) Do nothing and see how I go.
b) get it pressure tested---will do that next week or so and see what comes of that.
c) change head gasket and what else?

Thanks for the ideas JC.

Hopefully the pressure test will reveal something.

cheers

[disco gazza]

Booked in next Tuesday.
Let you know the results.

cheers

[disco gazza]

" UPDATE "

Had the cooling system checked and all fine.

When i get Timing belt done I will get the head gasket done .


cheers